Am I being jealous or was the obvious...obvious?

so last night my girlfriend of 3 months and I went to this really nice bar where they were playing live jazz music. it was a great atmosphere. my girlfriend and I were all cuddled up while the music was going and what not....then they called her up on stage (bc she sings) and after some cheering from me and the crowd she went up and sanged wonderfully. and in fact the drummer knew the song she sanged and chimed in (which made her even more comfortable while on stage). after she finished she recvd several compliments from everyone and was cheered.... even by the drummer who came by our table and sat and chatted with us. i noticed the drummer after awhile running out of things to talk about (and so did I) and there was the awkward silence, but my girlfriend showed definate interest and kept asking the questions (which was fine b/c she's a people person)....but after awhile i noticed "the look" in the drummers eyes and how his eyes locked onto my girl and well she "looked" the same..... i didnt want to immediately play jealous so i just went along with the evening...we all shared laughs and what not....but i noticed how the drummer would look at me when talking but then avert his eyes to my girl and stare much longer and when he noticed me catching his gaze he quickly avert his eys to the table or something......she was oblivious ( i assume). but the drummer then seemed more nervous and fidgety.... anyway his break was up he went back to the drums.....and well i noticed while he was playing he'd "steal" a look over to my girl.. .often..... and i noticed her even staring at him some times....and when i met his gaze he'd avert it to something else.....you know like that look of interest (is what it looked to me)..... then she got back on stage to sing agian (by request of the crowd). she sang the song "fever" and seriously through out the song not once did she look at me...she looked at the crowd...but made sure to look at the drummer, especially during the chorus.....at any rate while the drummer sat at our table she made sure to ask him for "his card". which he provided and apparently they intended on face booking eachother.... and he made sure to say "you guys email me" ....at any rate i know this sounds crazy....and well she is a likable person (that's why i'm with her) but i'm serious....it felt as if the two of them flirted with eachother right there in front of me.... and not flirting in the "obvious" sense but real subtle...... you know that look was the same look that she and I shared when we realized we shared chemistry when we first dated.